Electrical reversing controllerremotely adjustable



July 4, 1939. A, A, T m 2,164,958

ELECTRICAL REVERSING CONTROLLER-REMOTELY ADJUSTABLE Filed Feb. 17, 1938 2 Sheets-Sheet 1 A. A. STEIN July 4, 1939.

ELECTRICAL REVERSING CONTROLLER-REMOTELY ADJUSTABLE Filed Feb. 17, 1938 2 Sheets-Sheet 2 A iiorneys Patented July 4, 1939 ELECTRICAL REVERSING CONTROLLER REMOTELY ADJUSTABLE Albert A. Stein, Cold Spring, Minn.

Application February 17, 1938, Serial No. 190,988

11 Claims.

My invention relates to apparatus for controlling electric motors and particularly to remotely adjustable automatic motor reversing controllers.

In certain types of machinery a movable portion thereof is propelled in successively opposite directions in recurring cycles between the respective ends of a path of predetermined length by a reversible electric motor which is reversed each time said movable portion reaches an end of said path. In many instances the frequently recurring reversals of a motor in such service is effected by manipulation of a manually operated reversing controller or switch and hence necessitates constant attendance. Also, in such types of machinery, it is usually necessary to frequently alter the distance of travel of the propelled machine part and the positions of the ends of the path of travel thereof.

An object of my invention is to provide an automatic electrical reversing controller adapted for so controlling a reversible electric motor as to produce alternately forward and reverse operation of mechanism driven by said motor.

Another object is to provide such a controller which is self adjustable in response to manipulation of control means included therewith.

Yet another object is to provide such a controller which is electrically remote controllable for purposes of automatic self adjustment.

Still another object is to provide such a controller wherein the respective limits of movement of mechanism associated therewith for control thereby may be adjusted independently of each other.

A further object is to provide such a controller of light, compact, rugged and inexpensive construction and particularly flexible with respect to application thereof to various machines.

These and other objects and advantages of the 40 invention will more fully appear from the following description made in connection with the accompanying drawings, wherein like reference characters refer to the same or similar parts throughout the views, and in which:

Fig. 1 is a front view of an embodiment of my invention;

Fig. 2 is a sectional view taken along the line 2-2 of Fig. 1 as indicated by the arrows;

Fig. 3 is a sectional View taken along the line 3-3 of Fig. 1 as indicated by the arrows; and

Fig. 4 is an electrical connection diagram in accordance with which my controller may be arranged.

Referring to the drawings the parts of the illustrated embodiment of my invention are contained in and supported by a casing C having end Walls 5 and 6 and a bottom wall 1.

Strips 8 of suitable material are secured to the bottom of the bottom wall I and extend beyond the ends thereon and are bent downwardly to form mounting feet 8a.

The upper ends of the end Walls 5 and G are connected by brace members 9 which may be of angular cross section, as

shown.

A cover is provided forming a top wall gitudinally thereof.

The tubular members are constructed of electrically conductive material and are mounted on the upper ends of insulating posts 55 and it, which in turn are supported at their lower ends by bracket elements ll suitably secured to the end walls 5 and 6 of the casing C. Each of the tubular members is provided throughout its medial portion with slots Ma in its upper and lower sides.

Also each of the tubular members i4 is longitudinally split, as along the line Mb, so as to divide the tubular member [4 into respective upper and lower halves I40 and Md. At the lower end of each of the members I i a lug Me is formed in the upper half I40 and extends downwardly into the lower half Md. The lower end portion of each lug Me is apertured and is pivotally connected to the lower half bid of the member M by means of a pivot pin 14 so that the upper half Me of each of the members 14 is upwardly swingable relative to the corresponding lower half Md.

Each of the upper halves M0 is provided at its free end with a notched member [8 mounted thereon and comprising a hook. Means is provided for raising the upper half I 40 of each of the tubular members. Hi, this means preferably being of an electromagnetic nature so as to be electrically remote-controllable.

The preferred mounted on the end wall 6.

The solenoids I9 contain magnetic plungers I917 suitably connected to the respective hooks I 8 and the upper halves Mic. The means of connection to the hooks l8 consists in a pair of links 2| disposed parallel to each other and at opposite sides of the hook l8 and the lower end of the plunger I919. The links 2i are secured to the plunger 19b by means of a pin 22 passing through the upper ends of the links and through a suitable diametrical aperture in the lower end of the plunger I9b. Suitable means such as the cotter keys 23 disposed in diametrical apertures in the pin 22 are provided to retain the pin 22 in place and to retain the links 2! on the pin 22. A pin 24 is extending through apertured lower ends of the links El and through the notch of the hook l8. Cotter keys 25 are provided to retain the pin 24 in place and retain the links 2! on the pin 24.

Means is provided for normally retaining the upper halves Me of the tubular members 14 in closely parallel relation to the respective lower halves i401. For this purpose helical tension springs 23 are connected between the respective ends of the pin 24 and the respective ends of an anchoring pin 21 mounted on the brackets ll. Obviously the springs 26 will normally maintain the respective upper and lower halves of the tubular members in closely parallel relation and energization of the coil Illa, will cause upward movement of the plunger 19b to raise the upper half 840 of a tubular member I4 against the tension of the springs 23. To prevent electric connection between the springs 26 and the tubular members l4 aprons 28 formed of sheet insulating material and having apertures through their upper portions are mounted on the pin 24 as shown.

Electrical contact means movable longitudinally of the respective tubular members I4 in the interiors thereof are provided, and means is provided whereby the respective contact means will move in unison and may be connected to a moving part of a mechanism or machine to move in unison therewith. A pair of angular members 29 extending longitudinally of the casing C are mounted on the bottom wall I in spaced parallel relation so as to provide guide means for an element movable longitudinally thereof. A block Sill is provided and its lower portion is disposed between the angle members 29 to be guided thereby in movement longitudinally thereof. The block 3G is provided with an aperture extending horizontally and parallel to the angle members 29. The block is internally screw-threaded in the aperturecl portion thereof. An externally screw-threaded shaft 35 extending longitudinally of the casing C is screw-threadedly engaged at its medial portion in the block 30 and is journailed in bearings 32 and 33 mounted on the respective end Walls and B of the casing C. The right-hand end of the shaft 3! extends externally of the casing C to provide for connection of the shaft 3i to a mechanism. Obviously rotation of the shaft 3i will move the block 3!] Iongitudinally with respect to the guide formed by the angle members 29. A slab 34 of insulating material is mounted on the top of the block 3?, and upon the slab 34 is mounted a bar 35 of electrical conducting material bent to form respective brackets 35a extending to points below the respective tubular members l4. Each bracket is up turned and apertured at its free end to form a bearing 35b, and a shaft 36 is journalled in each of the bearings 35b. Each shaft 36 carries at its outer end an electrical contact finger 31 projecting upwardly through the longitudinal slots Ma of a corresponding one of the tubular members l4. The inner end of each shaft 36 carries an upwardly extending arm 38. Each arm 33 is provided at its upper end with a helical tension spring 39 connected with the arm 33 and an anchoring element 40 mounted on the member 35 in a direction from the arm 38 toward the upper end of the tubular member l4 associated with the arm 38. A stop pin 4| is provided for each of the arms 33, is mounted on a member 35, and is positioned to so limit movement of the arm 38 responsive to tension of the spring 39 that the arm 38 will normally remain in a vertically projecting position thereof. Above the member 35 and parallel to the shaft 3| an electrically conductive contact bar 42 is provided, the respective ends of the contact bar 42 being insulatedly mounted on the respective end walls 5 and 3. To provide an electrical connection between the finger carrying member 35 and the contact bar 42, an electrical contact finger 43 is mounted on the upper side of the member 35 and is of resilient nature and so shaped and proportioned as to bear against the lower side of the contact bar 42 and slide therealong as the block 30 is moved longitudinally of the casing C.

For cooperation with the contact fingers 3'! spherical electrical conductive elements 44 are placed within the respective tubular members M in positions up the inclines of the respective tubular members M from the contact fingers 31 associated with the respective tubular members l4. The contact fingers 31 and the spherical conductive elements 44 constitute electrical switches, the connections to the spherical conductive elements being provided through the conductive tubular members M. The spherical conductive elements 44 are of such diameter as to normally be clamped between the respective upper halves I40 and lower halves Md of the tubular members l4. When the solenoids H) are energized to raise the upper halves Me of the tubular members [4, the spherical elements 44 are released and are free to roll down the inclines of the tubular members [4 responsive to the pull of gravity. This rolling action will, of course, be terminated when the spherical elements 44 reach positions where they engage the corresponding contact fingers 3T. Releasing of the spherical elements 44 and rolling thereof responsive to gravity enables adjustment of my controller as will be explained later. Normally the spherical elements 44 are retained in fixed positions by the clamping action of the tubular member I 4. If the shaft 3i is rotated in one direction through a sufiicient distance by a moving part of a mechanism to which the shaft 3| is connected, one of the contact fingers 31 will reach engagement with the corresponding one of the spherical elements 44. The electrical switch comprised by the inter-engaged contact finger 31 and spherical element 44 may be utilized to operate an electrical control circuit for reversing an electric motor used to drive a mechanism to which the shaft 3! is mechanically connected. This will cause reversal in the direction of rotation of the shaft 3| whereupon the block 30 will move in a direction opposite to the direction in which it previously moved. If the remaining one of the contact fingers 37 engages the remaining one of the spherical elements 44, another reversal of the motor may be effected as described in connection with the first contact finger 31 and spherical element 44. The result will be that the motor will be periodically reversed to drive a mechanism first forwardly and then reversely in recurring cycles.

A flat bar 45 disposed in a vertical plane extends longitudinally of the interior of the casing C and is secured at its respective ends to the respective end walls 5 and 6 of the casing C, as by means of bolts 46. The bar 45 is provided for the purpose of mounting thereon auxiliary electrical apparatus for use in connection with the above described portions of my reversing controller.

Fig. 4 is an electrical connection diagram of the above described controller mechanism and auxiliary relays and devices associated therewith for use in controlling an electrical motor M. In the diagram of Fig. 4, a source of electrical energy is represented by a battery B. In this diagram means is shown for changing connections to the motor M responsive to operation of the above described parts of my controller, so as to cause periodic reversal of the motor M in recurring cycles, and means is also shown for manually controllingthe motor M during the process of changing the adjustment of my controller. Such an electrical circuit diagram as illustrated in Fig. 4 is suitable for use in my controller in cases where a machine having a reciprocating or rotating part is intended to be driven by a reversible electric motor in such a manner that the moving part of the machine will move in respective directions responsive to rotation of the motor M in respective directions. For such use of my controller the shaft 3| thereof may be connected by any suitable mechanical transmission means to the movable part of the driven machine so that the block 30 of my controller will move back and forth in unison with forward and reverse movement of the movable part of the machine.

A control station S which may be remote from other parts of my controller is provided and includes a pair of electrical switch elements 4'! and 48 such as push buttons or the like and a single pole double throw electric switch 49. For convenience in direction operation of the circuit, the respective ends of the battery B are designated as positive and negative by means of plus and minus signs. A pair of magnetic contactors 50 and 5| are provided in direct association with the motor M, and are connected therewith and with the battery B in a conventional circuit wherein actuation of the contactor 50 will cause rotation of the motor M in one direction, and actuation of the contactor 5| will cause rotation of the motor M in the other direction. Contactors 50 and 5| are provided with respective operating coils 50a and 5|a and sealing-in contacts 55b and Mb. The sealing-in contacts 50b and 5|b are constructed in accordance with the conventional practice and are closed coincidental with the closing of the main contacts 590 and 5|c of the respective contactors 50 and 5|. Contactor operating relays 52 and 53 are provided, these relays having respective lower pairs of contacts 52a and 53a which are normally closed and respective pairs of upper contacts 521) and 53b which are normally open. The relays 52 and 53 have respective operating coils 52c and 53c which, when energized, will operate the relays to open the lower contacts and close the upper contacts. With the relays 52 and 53 both de-energized neither of the contactor operating coils 50a and 5|a are energized, but actuation of the respective relays 52 and 53 through energization of their operating coils 52c and 530 will cause energization of the contactor operating coils 50a and 5Ia. The electrical connections between the contacts of the relays 52 and 53 and. the coils of the contactors 5|] and 5| are such that only one of the contactors 50 and 5| can be actuated at a time.

In normal operation of my controller the control station switch 49 is in its right-hand position so as to connect the positive side of the battery B to the contact bar 42 of my controller and incidentally to the contact fingers 31. One end of each of the relay operation coils 52c and 530 are connected to the negative side of the battery B. The remaining ends of the respective relay coils 52c and 530 are connected to the respective tubular members l4 and therethrough to the respective spherical conductive elements 44. Obviously as the pair of contact fingers 31 travel in alternate directions one finger will contact one of the spherical elements 44 at one end of the range of travel of the finger 31 to cause energization of one of the relay coils 52c and 530, resulting in closure of one of the contacts 55 and 5|. As the actuated one of the contactors 50 and 5| reaches its closed position, the sealing-in contacts 5% or 5|c thereof will be closed to complete a circuit between the contactor coil at the negative side of the battery to seal-in the coil circuit of the contactor. Operation of one of the relays 52 or 53 will cause energization of the corresponding contactor and also, by opening of the lower relay contacts, the coil circuit of the previously closed one of the contactors will be interrupted to cause opening of that contactor prior to closure of the newly actuated contactor. Reversal of the motor M due to the change in position of the respective contactors 5|] and 5| produce reversal of the direction of movement of the movable part of a machine to which the shaft 3| of my controller is connected, and hence causes reversal in the direction of movement of the contact fingers 31. been in engagement with a corresponding one of the spherical elements 44 is soon withdrawn from such engagement but the contactor closed from such engagement remains closed by current feeding through the sealing-in contacts of the closed contactor. When the pair of contact fingers reach the other end of their limit of movement and one of the contact fingers 31 engages the remaining one of the spherical elements 44, an operation similar to that described above will occur to again reverse the motor M.

The above description pertains to normal operation of the reversing controller illustrated in the drawings and provision is also made for manually controlling the controller in such manner as to effect repositioning of one or both of the spherical elements 45 with respect to the corresponding ones of the tubular members I4 so as to alter the distance of travel of the movable part of a machine driven by the motor M and mechanically connected to the shaft 3| of my controller. For such adjusting procedure the switch 49 of the control station S is shifted to its left-hand position to break the connection between the positive side of the battery and the contact bar 42, and thus prevent control of the motor M by the contact fingers 3] and spherical elements 44. A series of auxiliary relays 54, 55, 56 and 51 having coils 54a, 55a, 55a, and 51a are provided. The relays 54, 55, and 55 are provided with normally open respective contacts 54b, 55b, and and 5% which are respectively closed responsive to energization of the respective coils 54a, 55a, and 56a. The relay 5! has a movable contact element 51b nor- The finger 31 which has just mally engaged with a stationary contact element 510 and shiftable upon energization of the coil 51a out of engagement with the contact E'lc and into engagement with a contact 57d. The circuit is so arranged that shifting of the switch 49 to the left causes energization of the coils E la and 51a. The contacts of the relay 5'! are so connected that energization of the coil 51a will interrupt the supply of electrical energy to the sealing-in circuits of the contactors 55 and El. The contacts of the relays 5 5 and 57 are so arranged in the circuit as to connect one terminal of each of the solenoid coils lQa to the negative side of the battery B. The contacts of the relays 55 and 55 are connected in respective circuits from the positive side of the battery B to the remaining terminals of the respective solenoid coils Na and to the terminals of the respective relay coils 52c and 530 so that closure of the contacts 551) will energize the relay coil 53 and a corresponding one of the solenoid coils llb, and closure of the relay contacts 56?) will cause energization of the relay coil 52c and the remaining one of the solenoid coils l9a. The coils 55a and 55a of the relays 55 and 56 are connected to be respectively energized by closure of the respective push-button switches All and 4-8.

In adjusting my controller, as mentioned above, the switch 69 is shifted to the left to energize the relays 54 and 57 and thereby set up circuits whereby the solenoid coils Mia and i819 are connected for operation responsive to manipulation of the respective push-buttons 47 and Q8. Shifting of the switch 49 to the left also connects the push-buttons 41 and 68 to the positive side of the battery 13 so as to retain the push-buttons if and 3-8 and the relays 55 and 5toperative. To change the position of the lower spherical element M, as indicated in Fig. 4, the push-button 3? is pressed, energizing relay 55 and resulting in energization of the relay coil 530 in the corresponding solenoid coil Illa. Energization of the solenoid coil lQa releases the spherical element M which will then roll down into engagement with the corresponding contact finger 37. Energization of the relay coil 530 results in operation of the motor M to move the contact finger 3'l to the left. The released one of the spherical elements M will then be pushed up the incline of the corresponding tubular memher it by the corresponding one of the contact fingers 3?. When the operator observes that the machine driven by the motor has reached the newly desired limit of movement in the direction involved, he releases the push-button ll which de-energizes the relay coil 530 to stop the motor M and de-energizes the corresponding one of the solenoid coils Ida, to produce retention of the newly shifted lower spherical element 3G in its newly acquired position. To set the upper spherical element M in a newly desired position, the push-button 48 is operated and setting of the upper spherical clement M is accomplished in a manner similar to the above described resetting of the lower spherical element :36. When both spherical elements i l have been set in accordance with the desired new range of movement the switch Ml may be shifted to the right to re-establish connections producing alternate directions of operation of the motor M and the machine driven thereby in recurring cycles.

From the above it should be apparent that I have invented an electrical reversing controller adapted for controlling an electrical motor to produce alternate directions of rotation of the motor and alternate directions of movement of a moving part of a machine driven by the motor in recurring cycles. It is to be further noted that my controller is adapted for automatic adjustment thereof responsive to operation of an electrical remote control circuit. Obviously the controller equipment contained within the casing C may be disposed remotely from the control station S and remotely from the battery B and the contactors 5i and 5!. The shaft 3! of the controller may be connected to a moving part of a machine by any suitable mechanical transmission means and such mechanical transmission means may, if desired, be of such nature that the casing C may be located relatively remote from the machine from which the shaft Si is driven.

While I have shown my reversing controller as applied to an electric motor and electrical control means therefor, it should be apparent that other types of driving means for a machine may be readily controlled by my controller through any desired conventional forms of electrically operatable control means.

It will, of course, be understood that various changes may be made in the form, details, arrangement and proportions of the various parts without departing from the scope of my invention.

What is claimed is:

l. A reversing controller for mechanism having electrically controllable apparatus for propelling a movable portion thereof in successively opposite directions including, a guide of which one end is disposed at a higher level than the other, an electrical contact element arranged for movement generally longitudinally of said guide and adapted to be connected to an oscillatable portion of a mechanism for movement in unison therewith, an electrically conductive element supported by said guide in longitudinally movable relation thereto upwardly of said contact element for engagement thereby and cooperation therewith in constituting an electrical switch unit adapted to be connected in a control circuit of an electrically controllable apparatus said conductive element being movable downwardly of said guide responsive to gravity, and means for normally restraining said conductive element from movement longitudinally of said guide said means being releasable to enable movement of said conductive element independently thereof.

2. A reversing controller for mechanism having electrically controllable apparatus for propolling a movable portion thereof in alternate directions in recurring cycles including, a pair of guides each having one end thereof disposed at a higher level than the remaining end thereof, a pair of electrically conductive elements carried by the respective guides in longitudinally movable relation therewith, said elements being movable downwardly of the corresponding guides responsive to gravity means associated with said guides for normally restraining said elements from movement relative thereto, said means being releasable to enable movement of said elements independently thereof, a pair of electrical contact elements arranged for movement longitudinally of the respective guides and engagement with said respective conductive elements to form, in conjunction therewith, respective electrical circuit-controlling means adapted for use in controlling electrically controllable reversible apparatus, and means so interconnecting said contact elements that one will move longitudinally upwardly as the other moves longitudinally downwardly of the respectively corresponding guides, said contact elements being adapted to be connected to a movable portion of a mechanism for movement in unison therewith and said conductive elements being disposed in the respective guides upwardly of the respectively corresponding contact elements.

3. A reversing controller for mechanism having electrically controllable apparatus for propelling a movable portion thereof in alternate directions in recurring cycles including, a pair of oppositely inclined guide members disposed in respective substantially parallel vertical planes, a pair of electrical contact elements arranged for movement in unison longitudinally of said pair of members and respectively associated with the respective members, said contact elements being adapted to be connected to a movable portion of a mechanism for movement in unison therewith, a pair of electrically conductive elements supported by the respective members up the slopes thereof from said contact elements for engagement by said contact elements and co-operation therewith in constituting respective electrical switch units adapted to be connected in control circuits of an electrically controllable propelling apparatus said conductive elements being movable downwardly of the corresponding guide members responsive to gravity, and releasable means for restraining said conductive elements from movement longitudinally of said members.

4. A reversing controlled for mechanism having electrically controllable apparatus for propelling a movable portion thereof in alternate directions in recurring cycles including, a pair of oppositely inclined guide members disposed in respective substantially parallel vertical planes, a pair of electrically conductive elements supported by said respective members and adapted to travel down the slopes thereof responsive to gravity, releasable means associated with each of said guide members for normally restraining the element thereon from movement longitudinally thereof, a body movable longitudinally of said members and adapted to be connected to a movable portion of a mechanism for movement in unison therewith, a pair of electrical contact fingers carried by said body and situated for engagement with said respective elements to form, in conjunction therewith, respective electrical circuit-controlling means adapted for use in controlling electrically controllable reversible apparatus, said elements being situated up the slopes of the respective corresponding members from the respective corresponding contact fingers.

5. A reversing controller for mechanism having electrically controllable apparatus for propelling a movable portion thereof in alternate directions in recurring cycles including, a pair of oppositely inclined tubular members disposed in respective substantially parallel vertical planes, a pair of spherical, electrically conductive elements situated within said respective members and movable down the slopes thereof responsive to gravity, the medial portion of each of said members having a longitudinally extending slot therein, releasable means associated with each of said members for normally restraining the spherical element therewithin from movement longitudinally thereof, a body movable longitudinally of said pair of members and adapted to be connected to a movable portion of a mechanism for movement in unison therewith, a pair of electrical contact fingers carried by said body, and prdjiecting through said respective slots for engagement with the respective spherical elements to form in conjunction therewith respective electrical circuitcontrolling means adapted for use in controlling electrically controllable reversible apparatus, said spherical elements being situated up the slopes of the respective tubular members from the respective contact fingers.

6. A reversing controller for mechanism having electrically controllable apparatus for propelling a movable portion thereof in alternately opposite directions in recurring cycles including, a pair of electrically conductive tubular members having respective, oppositely inclined axes disposed in respective substantially parallel vertical planes, a pair of spherical, electrically conductive elements contained within said respective members and being movable down the slopes thereof responsive to gravity, the medial portion of each of said members having a longitudinally extending slot therein and each of said members being longitudinally divided into two parts, means interconnecting the lower ends of the respective parts of each of said members to permit swinging movement of one part relative to the other, means yieldably urging the respective parts of each of said members together to normally grip the corresponding spherical element therebetween, means associated with each of said members operatable to spread the parts thereof apart to free the corresponding spherical element for movement longitudinally of said member, a body movable longitudinally of said pair of members and adapted to be connected to a movable portion of a mechanism for movement in unison therewith, a pair of electrical contact fingers carried by said body and projecting through the slots of the respective tubular members for engagement with the respective spherical elements to co-operate with the same and said members in constituting respective electrical circuit-controlling means adapted for connection in circuit with electrically controllable reversible apparatus, said spherical elements being situated up the slopes of the respective tubular members from the respective contact fingers.

'7. A reversing controller for mechanism having electrically controllable apparatus for propelling a movable portion thereof in alternately opposite directions in recurring cycles including, a pair of electrically conductive tubular members having, oppositely inclined axes disposed in respective generally parallel vertical planes, a pair of spherical, electrically conductive elements contained within said respective members and movable down the slopes thereof responsive to gravity, the medial portion of each of said members having a longitudinally extending slot therethrough vertically aligned with the axis thereof and each of said members being longitudinally divided into respective upper and lower halves thereof, means interconnecting the lower ends of the respective halves of each of said members to permit swinging movement of one half relative to the other, means yieldably urging the respective halves of each of said members together to normally grip the corresponding spherical element therebetween, means associated with each of said members operatable to spread the halves thereof apart to free the corresponding one of said spherical elements for movement longitudinally of said member, a body movable longitudinally of said pair of members and adapted to be connected to a movable portion of a mechanism for movement in unison therewith, and a pair of electrical contact fingers carried by said body and projecting through the slots of the respective tubular members for engagement with the respective spherical elements to co-operate with the same and said members in constituting respective electrical circuit-controlling means adapted for connection in circuit with electrically controllable reversible apparatus, said spherical elements being situated up the slopes of the respective tubular members from the respective contact fingers.

8. A reversing controller for mechanism having electrically controllable apparatus for propelling a movable portion thereof in alternate directions in recurring cycles, including, a pair of electrically conductive tubular members having oppositely inclined respective axes disposed in respective substantially parallel vertical planes, a pair of spherical, electrically conductive elements contained Within said respective members and movable down the slopes thereof responsive to gravity, the medial portion of each of said members having a longitudinally extending slot therethrough vertically aligned with the axis thereof and each of said members being longitudinally divided into respective upper and lower halves thereof, the lower half of each of said members being fixedly mounted, means interconnecting the lower ends of the respective halves of each member for vertical swinging movement of the upper half relative to the lower half, resilient means urging the respective halves of each of said members together to normally grip the corresponding spherical element therebetween, electromagnetic means energizable to lift the upper halves of the respective members to free the respecting spherical elements for movement down the slopes of the respective members, a body movable longitudinally of said pair of members and adapted for connection to an oscillatable body for movement in unison therewith, and a pair of electrical contact fingers carried by said body and projecting through the slots of the respective members for engagement with the respective spherical elementsrto co-operate with the same and said members in constituting respective electrical circuit-controlling means, said circuit controlling means being connected with said respective control circuits, and said spherical elements being situated up the slopes of the respective tubular members from the respective contact fingers.

9. A reversing controller for mechanism having electrically controllable apparatus for propelling a movable portion thereof in successively opposite directions including, an elongated, longitudinally apertured guide member disposed in other than a horizontal position, an electrical contact member having a portion thereof situated within and movable longitudinally of said guide member, said contact member being adapted for connection thereof to an oscillatable body for motion in unison therewith, an electrical contact element carried in said guide member above said contact member for engagement therewith, said contact element being movable longitudinally of said guide member and movable downwardly thereof responsive to gravity, and releasable means for normally restraining said contact elcment from movement longitudinally of said guide member, said contact member and said contact element constituting an electrical switch.

10. The combination defined in claim 9, and electrically actuatable means for operating said restraining means.

11. A reversing controller for mechanism having electrically controllable apparatus for propelling a movable portion thereof in successively opposite directions including, an elongated guide member disposed in other than a horizontal position, an electrical contact member having a portion thereof situated within and movable longitudinally of said guide member, said contact member being adapted for connection thereof to an oscillatable body for motion in unison therewith, an electrically conductive spherical element carried by said guide member above said contact member and adapted for movement toward the lower end of said guide member responsive to gravity, and releasable means for normally restraining said conductive element from movement longitudinally of said guide member, said contact member and said conductive element together comprising an electrical switch.

ALBERT A. STEIN. 

